THE INHIBITORY EFFECTS OF siRNA EXPRESSION VECTOR ON THE TAURINE BIOSYNTHETIC RATE-LIMITING ENZYME-CSD GENE OF RAT H9C2 CARDIAC MYOBLASTS

Objective To investigate the inhibitory effects of RNAi(RNA interference) on CSD expression in rat H9c2 cells.Methods Four siRNAs expression vectors and one negative control siRNA expression vector were constructed to be targeted directly at cysteine sulfinate deacrboxylase(CSD) gene(Biomics Biotechonolgies,China).Then the recombinant plasmids siRNA1#、siRNA2#、siRNA3#、siRNA4# and siRNA-Neg were transfected into H9c2 cells with liposomes Lipofectamine 2000.After transfection,the transfection efficiency was observed under fluorescent microscopy.CSD mRNA and protein expression were examined using RT-PCR and Western blot.MTT assay was performed to detect the state of cell proliferation.Results The transfection efficiency was about 70%.Recombinant plasmid siRNA1# significantly decreased the expression of CSD at gene and protein levels(P0.05).However,the recombinant plasmid siRNA4# had no significant inhibition effect on CSD expression(P0.05).Cell proliferation in the transfected cells was inhibited obviously by siRNA1# and siRNA2# plasmid compared with untransfected cells and negative control cells at 48 h,72 h(P0.05).Conclusion The siRNA1# recombinant plasmid could effectively inhibit the expression of CSD in rat H9c2 cells and proliferation of H9c2 cells,which will benefit the further study on the function of CSD and taurine in cardiocytes metabolism.